Hello! I just took my 2013 Prius, 145k miles, to the shop for a O2 sensor replacement. This is a new shop to me but came recommended from a friend and seemed to have good reviews, etc. They called me and told me I had severe subframe rot and the car wouldn't pass inspection. I live in New England, I believe that my car could have severe rust. But this seems really sudden. No one has ever mentioned this issue to me. I've had mechanics do oil changes and other maintenance in the past year. It passed inspection 18 months ago. Three years ago I did a prepurchase inspection with a mechanic and he didn't mention rust as a potential issue at all. Is subframe rot a thing that would appear suddenly? He quoted me $2k-4k for the repair and was saying my car might not be worth more than that (it seems like it's worth at least $7k). He kept talking about things that go wrong on older cars like the water pump and catalytic converter. Honestly, it felt like the guy was trying to get me to trade in my car (they also do auto sales). Is this something I should actually consider getting rid of this car for? Otherwise, it's been very reliable and I had planned to drive it for another four or five years or as long as it kept driving. Thanks!
welcome! you have to be careful with things like this. sub frame rot is a thing, but fairly rare. it could appear suddenly after what appeared to be surface rust previously. you need at least a second opinion, if not more. he could be correct, or he could be trying to scare you. try to find a mech who doesn't sell cars. ask them to put it on the lift and take a careful look around and get their opinion. as an aside, a 12 year old prius with 145k could be a ticking time bomb in regard to other costly repairs, or you could get another 100,000 relatively repair free miles. but there's no way to know. keep in mind the battery, brake actuator and head gasket as you do your due diligence. all the best!
Thanks for your thoughts! Yeah, I'm going to get a second opinion before I make a decision. It's just so unexpected because I would have guessed this was the least rusty car I've ever owned-- but I guess it's hard to know without knowing what you're looking for and putting it on a lift.
You actually have to look for sub-frame rot. An oil change person is only looking for the oil drain plug - Not looking for other problems. Did that shop show you pictures of your problem areas. It's as easy as pulling out their cell phone and taking a picture or video. Get a second opinion......
You roll the car up on ramps you see all that frame material facing down hit it with a rubber mallet pieces if rust may fall watch out . If you dent or knock holes it's over pretty much it don't take much but a pair of ramps and a mallet
South Main Auto is a good channel and he does NY State inspections. He says most cars are rotted out in 10 years unless routinely undercoated with something like Fluid Film. In fact he sometimes won't put them on a lift fearing they might collapse. Another interesting channel in Rochester NY fixes up and sells older gen2 and some gen3 Prii. He buys them from southern states without rust concerns and makes a big deal of that fact. An example:
